1. Field of the Invention
This invention relates to an antifouling resinous composition having as an active component thereof, a resin containing a metal carboxylate in the molecular unit thereof and methods for the production of resins.
2. Description of Related Art
Prior to the present invention, resins which have a metal salt structure as a molecular unit have been studied for potential as a prospective binder for antifouling paints and have been reduced to practice. The most common of these resins are carboxylates of tin. Since carboxylates of tin have exhibited toxicity problems, carboxylates of copper or zinc have gained wider use recently. Both of these resins possess no free hydroxyl groups and are represented by the following general formula (A) or (B). EQU R.sub.p --COO--M--(R).sub.n (A) EQU R.sub.p --COO--M--(OCOR).sub.n (B)
wherein R.sub.p represents a basal resin, M represents a divalent metallic atom, R represents a hydrocarbon group, and n represents an integer in the range of 1-3.
When a hydroxyl group is present, the resin inevitably gels in the synthesis process, thereby producing a defective antifouling resinous composition.
The synthesis of compound (A) is generally expensive. In addition, the synthesis of compound (B) is likely to produce mixtures of various compounds because two or more hydroxyl groups have only small differences in reactivity, and as a consequence, the product requires very expensive purification.